Importance: The block of primary (uncut) forest of approximately 35,000 acres in size is considered by the Michigan Natural Features Inventory to be the "biggest and best tract of virgin Northern Hardwoods in North America" and it is certainly one of the largest relatively undisturbed northern hemlock-hardwood forests west of the Adirondacks. The federal government has recognized the area as a National Natural Landmark.

The Porcupine Mountains themselves arise abruptly from Lake Superior to form a 12 mile long escarpment which parallels the lakeshore for a distance of 1.5 miles. At 2 billion years old, the mountains are a section of one of the oldest mountain chains in the world. On the landward side of the escarpment is Lake of the Clouds, which is one of the spectacular views to be found from high peaks in the area. On a clear day, one may see more than 25 miles to the west.

Noted for its magnificent forests, scenic vistas, over 90 miles of hiking trails, and striking geologic formations, the park is also home to a number of endangered, threatened and special concern species including small blue-eyed mary, ram's head ladyslipper, Hooker's fairy-bells, slender cliff brake, male fern, gray wolf, wood turtle, peregrine falcon, merlin, and bald eagle. In addition, visitors can see excellent examples of wave-cut beaches carved by former glacial lake shore lines. .